interface A {
    void test1();
}

interface B {
    void test2();
}

interface C {
    default void test3() {
        System.out.println("test3");
    }
}

// 接口是多继承的
interface D {

}

class E implements D {
    @Override
    public void test1() {
        System.out.println("test1");
    }

    @Override
    public void test2() {
        System.out.println("test2");
    }
}


public class Task {
    public static void main(String[] args) {
        E e = new E();
        e.test1();
        e.test2();
        e.test3();
    }
}